Implantable medical devices, such as Implantable Pulse Generators (IPG's) used in implantable Cardiac Rhythm Stimulator (CRM) devices and Neurostimulator devices, typically have connector contacts that establish electrical connection between the IPG and the lead which directs the stimulus to the target area in the body. A plurality of connector contacts as used in both CRM and Neurostimulator devices range from 3 to 7 contacts that are stacked in-line. The contacts must be separated electrically by a dielectric insulator seal. The seal must also prevent the migration of body fluids between the electrical contacts of the IPG. Another desirable characteristic of the seals and possibly the contacts is adequate sealing force around the lead to maintain body fluid sealing to the lead while still providing acceptable insertion force. Exemplary IPGs and in line header connectors are disclosed in Ser. No. 11/839,103, filed Aug. 15, 2007, entitled Connector Assembly for Use with Medical Devices; Ser. No. 12/062,895, filed Apr. 4, 2008, entitled Connector Assembly for Use with Medical Devices; and Ser. No. 12/100,646, filed Apr. 10, 2008, entitled Integrated Header Connector System, the contents of each of which are expressly incorporated herein by reference.
The process of implanting an IPG of the CRM or Neurostimulator type typically requires a doctor to insert the stimulator lead into the IPG header containing a plurality of in-line contacts and seals. A typical commercially available lead is flexible by nature because it is made up of alternating metallic contact rings and separating dielectric spacers between the contact rings. Additionally, the lead is typically about 0.050 inches in diameter, which miniature size adds to its flexibility. It is therefore desirable to provide a device in which the force to insert the lead into the IPG header with its contacts and seals be appropriate for a miniature size lead. It is also desirable to formulate a method for reducing insertion force between a lead and an in line header connector. If the insertion force is too high, the lead may buckle and become difficult if not impossible to insert into the header assembly of the IPG. The need for low insertion force and adequate sealing therefore becomes even more important on modern neurostimulators where seven (7) or more alternating contacts and seals are used in line or as an integrated stack for each lead. In general, it is desirable to have an in-line connector as shown and described and/or to have systems and methods for using the same.